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21.
Semelka RC Custodio CM Cem Balci N Woosley JT 《Journal of magnetic resonance imaging : JMRI》2000,11(2):141-148
We reviewed our 8.5 year experience with magnetic resonance imaging (MRI) in the demonstration of neuroendocrine tumors of the pancreas using precontrast fat-suppressed T1-weighted, fat-suppressed T2-weighted, and serial post-gadolinium T1-weighted images, to describe the spectrum of appearances of these tumors. All MR examinations of patients with histologically proven neuroendocrine tumors were retrospectively reviewed. Histological type, tumor location, tumor diameter, signal intensity on precontrast images, enhancement patterns, and presence and appearance of metastases were determined. Twenty-two patients had histologically proved neuroendocrine tumors detected by MRI over the 8.5 year period. Histological types were gastrinoma (n = 8), insulinoma (n = 3), glucagonoma (n = 2), somatostatinoma (n = 1), VIPoma (n = 1), ACTHoma (n = 1), carcinoid (n = 1), and five untyped tumors. Primary tumors ranged in diameter from 1 to 6.2 cm. There was one histopathology-proven false-positive neuroendocrine tumor. The positive predictive value for MRI in the detection of these tumors was 96%. The most common appearance on precontrast images was low signal intensity on T1-weighted images and high signal intensity on T2-weighted images, which was observed in tumors in 18 of 22 patients. Moderate or intense early enhancement of all or portions of the primary tumors was observed in tumors in 19 of 22 patients either as uniform homogeneous, ring, or diffuse heterogeneous enhancement. Enhancement was minimal on these images in the other three patients. Gastrinomas enhanced in a ring pattern in 7 of 8 patients whereas the majority (9 of 11 patients) of noninsulinoma-nongastrinoma and untyped tumors enhanced in a diffuse heterogeneous fashion. Liver metastases were present in 13/22 patients including 3/8 with gastrinoma and 9/11 with noninsulinoma-nongastrinoma tumors. Most neuroendocrine tumors of the pancreas are low signal intensity on fat-suppressed T1-weighted images and moderately high in signal intensity on fat-suppressed T2-weighted images, although variations do exist. Tumors most often enhance in an early moderately intense fashion. Gastrinomas are often different in appearance than other neuroendocrine tumors in that they usually enhance in a ring fashion whereas nongastrinoma-noninsulinoma tumors usually enhance in a heterogeneous fashion. 相似文献
22.
The technical name for a surgical sponge left in the body of a patient is inadvertent “gossypiboma.” The word is derived from the Latin word Gossypium for cotton and from the Kiswahili word boma for “place of concealment.” These retained sponges were first seen as “textilomas,” but were renamed “gossypiboma” in 1978. The first case was reported by Wilson in 1884. These are rarely are retrieved in the literature, because of legal complications. A higher incidence of retained laparotomy sponges has been reported in association with gynecological procedures. We report a case of gossypiboma in the 38th week of pregnancy that imitated an ovary neoplasm. 相似文献
23.
Dane B Dane C Sivri D Kiray M Cetin A Yayla M 《Acta obstetricia et gynecologica Scandinavica》2007,86(6):666-670
BACKGROUND: This study was planned to evaluate the efficiency of the 11-14 week scan in detecting fetuses with major fetal structural abnormalities. METHODS: Some 1,290 pregnant women were submitted to a routine ultrasound scan between the 11th and 14th week after the detection of the fetal viability. The fetal anatomy was examined transabdominally, and in suspected cases transvaginally. Following the scans, the patients were examined in the second or third trimester of pregnancy. Fetal structural abnormalities classified as major and early onset were noted. Isolated choroid plexus cysts, cardiac defects not requiring treatment, mild ventriculomegaly, and mild renal pelviectasis in second trimester were not included. RESULTS: Twenty-four (1.86%) fetuses with various defects were identified, and 17 of these were diagnosed at the 11-14 week scan. The antenatal ultrasound detection rate of the fetuses with major anomalies was 95%, and 70% were detected in the first-trimester assessment. Four cardiac defects associated with genetic syndromes or requiring operation were included (0.31%) in this series. Two of the fetuses with cardiac defects (50%) had an increased nuchal translucency thickness. In this group, none of the fetuses with karyotype anomalies was born alive. CONCLUSIONS: The first-trimester scan is important in routine antenatal care for early detection of fetal defects, and determination of the fetuses at risk of cardiac anomalies and genetic syndromes. 相似文献
24.
Vicdan K Işik AZ Akarsu C Sözen E Cağlar G Dingiloğlu B Tuncay G 《European journal of obstetrics, gynecology, and reproductive biology》2007,134(1):79-82
OBJECTIVE: The purpose of this study was to determine the incidence of retained embryos and its impact on pregnancy outcome in the absence of known risk factors like blood and mucus in the transfer catheter. The factors that could be associated with embryo retention were also investigated. STUDY DESIGN: The results of all embryo transfer procedures performed at Ankara IVF Center between January 2003 and December 2005 were analyzed retrospectively. Three hundred and five embryo transfers, in which the transfer catheter was contaminated with blood or mucus, were excluded and the remaining 1,454 embryo transfers, with clean catheter, were enrolled into the study. Both fresh (n=1,422) and frozen (n=32) embryo transfers were included. RESULTS: The overall incidence of retained embryos during study period was 2.8% (41/1,454) following a clean initial embryo transfer. The mean age of the female partner, mean number of retrieved oocytes, MII oocytes, fertilized oocytes and the embryos transferred were similar in patients with and without retained embryos. The 1,454 embryo transfers performed during the study period resulted in 712 pregnancies (49%), of which 639 proved to be clinical pregnancies with a rate of 44%. The implantation rate was 22.8%. Pregnancy outcomes including positive beta-hCG (58.5% versus 48.7%), biochemical (4.7% versus 5.1%) and clinical pregnancy rates (53.6% versus 43.6%), implantation rate (24% versus 22.7%) and multiple pregnancy rate (36.3% versus 44.7%) were not significantly different between patients with and without retained embryos. An influence of individual physicians and embryologists on the frequency of retained embryos was not detected. The type of embryo transfer catheter used did not show any difference in terms of embryo retention. The cleavage stages of embryos were not different between groups. Although it was not statistically significant, the number of embryos transferred appeared to be a potentially confounding factor for retained embryos (p=0.053) and it might be significant in a slightly larger sample. When transfer of one or two embryos was compared to three or more embryos, the likelihood of retained embryos increased from 1.2% (4/321) to 3.2% (37/1,133). CONCLUSION: Retained embryos in the transfer catheter and immediate retransfer of them have no adverse impact on clinical pregnancy and implantation rates unless other previously reported signs of difficult transfer are also observed. 相似文献
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27.
Yasemin Giles enyürek Yaln can smail Cem Sormaz ükran Poyrazolu Fatih Tunca 《Journal of clinical research in pediatric endocrinology》2022,14(2):196
Objective:This study aimed to evaluate the role of risk stratification by the American Thyroid Association (ATA) pediatric thyroid cancer risk levels and BRAFV600E mutation to predict the response to treatment in papillary thyroid cancer (PTC) patients ≤18 years old.Methods:Clinical outcomes during a median period of 6 (2-21.8) years were assessed in 70 patients, according to ATA pediatric risk stratification, BRAFV600E mutation status, and dynamic risk stratification (DRS) at final follow-up.Results:Of 70 patients, 44 (63%), 14 (20%), and 12 (17%) were classified initially as low-, intermediate-, and high-risk, respectively. BRAFV600E mutation analysis data was available in 55 (78.6%) patients, of whom 18 (32.7%) had the BRAFV600E mutation. According to the final DRS, 61 (87%), two (3%), six (9%), and one (1%) patients were classified as an excellent, incomplete biochemical, incomplete structural, and indeterminate response, respectively. All ATA low-risk patients showed excellent response to treatment, whereas the rate of excellent response was 65.4% in intermediate- and high-risk levels (p<0.001). The rates of excellent response in BRAFV600E positive and negative patients were 83% and 92%, respectively (p=0.339). The rate of locoregional recurrence was significantly higher in BRAFV600E positive vs negative patients (33.3% vs 2.7% respectively, p=0.001).Conclusion:ATA pediatric risk stratification is effective in predicting response to treatment in PTC patients ≤18 years old. The presence of BRAFV600E mutation was highly predictive for recurrence but had no significant impact on the rate of excellent response to treatment at final follow-up. 相似文献
28.
Yusuf Cem Yilmaz Sefik Can Ipek Muhammet Derda Ozer Tugba Celebi 《Indian journal of ophthalmology》2022,70(5):1556
Purpose:To evaluate corneal densitometry (CD) of patients with arcus senilis (AS) and its association with the serum lipid markers.Methods:This is a cross-sectional, case-control study. The AS diagnosis was made clinically. Forty-five eyes of 45 patients with AS and 38 eyes of 38 age-matched control subjects with no noticeable AS were enrolled in the study. All participants underwent detailed ophthalmologic examination along with corneal Scheimpflug imaging with CD measurement. The evaluated serum lipid markers of the participants included total cholesterol, triglyceride, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and very-low-density lipoprotein (VLDL). The Spearman correlation analysis was used to correlate the serum lipid values and the CD. P < 0.05 was defined as statistically significant.Results:The male to female ratio was 26/19 and 14/24 in the study and control groups, respectively (P = 0.057). The mean age was 59.56 ± 8.7 and 56.47 ± 8.6 years in the study and control groups, respectively (P = 0.117). The mean total CD values in the zones extending from 2 to 12 mm were higher in the study group than in the control group (P < 0.001). The serum HDL level was found to be significantly decreased in the study group compared to the control group (P = 0.048 and Z = −1.976). There was a significant positive correlation between the serum triglyceride level and the CD value of the outermost zone (10–12 mm) (r = 0.334 and P = 0.025).Conclusion:The CD of patients with AS was found to increase not only in the peripheral zone but also in the cornea’s paracentral zone compared to the healthy controls. The serum triglyceride level should give an insight into the intensity of arcus senilis. The serum HDL levels were decreased in patients with AS. 相似文献
29.
The added value of the apparent diffusion coefficient calculation to magnetic resonance imaging in the differentiation and grading of malignant brain tumors 总被引:14,自引:0,他引:14
Bulakbasi N Guvenc I Onguru O Erdogan E Tayfun C Ucoz T 《Journal of computer assisted tomography》2004,28(6):735-746
OBJECTIVE: ADC calculation can improve the diagnostic efficacy of MR imaging in brain tumor grading and differentiation. METHODS: Apparent diffusion coefficient (ADC) values and ratios of 33 low-grade (23 astrocytomas, 10 oligodendrogliomas) and 40 high-grade (25 metastases and 15 high-grade astrocytomas) malignant tumors were prospectively evaluated. RESULTS: Tumoral ADC values (r=-0.738, P <0.000) and ratios (r=-0.746, P < 0.000) were well correlated with higher degree of malignancy and quite effective in grading of malignant brain tumors (P < 0.000). By using cutoff values of 0.99 for tumoral ADC value and 1.22 for normalized ADC ratio, the sensitivity of MR imaging could be increased from 72.22% to 93.75% and 90.63%, the specificity from 81.08% to 92.68% and 90.24%, PPV from 78.79% to 90.91% and 87.88%, and NPV from 75.00% to 95.00% and 92.50%, respectively. CONCLUSION: ADC calculation was quite effective in grading of malignant brain tumors but not in differentiation of them and added more information to conventional contrast-enhanced MR imaging. 相似文献
30.